Enhanced oxygen reduction catalytic performance of PtNi alloy through modulating metal-support interaction

Tuning metal-support interaction had been regarded as an effective strategy to adjust the electronic structure, catalytic activity and durability of supported metal catalysts. Herein, we design PtNi alloy on nitrogen-doped carbon and SnO2 dual-support and modulate the metal-support interaction. SnO2/PtNi/NC presents strongly coupled SnO2-PtNi-NC interface with lattice overlap of SnO2 (200), Pt (111), Pt (200), and graphitized carbon, along with enhanced electron transfer. SnO2/PtNi/NC has an improved catalytic activity and enhanced stability for oxygen reduction reaction. SnO2/PtNi/NC catalyst had a half-wave potential of 0.886 V versus reversible hydrogen electrode (RHE) in an acidic solution, higher than PtNi/NC (0.785 V vs. RHE) and commercial Pt/C (0.846 V vs. RHE). Furthermore, the current retention of SnO2/PtNi/NC (87.3 %) is also larger than that of commercial Pt/C (56.8 %) and PtNi/NC (19.8 %) after 1000 times start-stops. This study sheds light on the understanding effect of metal-support interaction on the durability of heterogeneous electrocatalysts.

Automated summary

In this study, PtNi alloy on nitrogen-doped carbon and SnO2 dual-support was designed to modulate the metal-support interaction, resulting in improved catalytic activity and stability for oxygen reduction reaction. The SnO2/PtNi/NC catalyst exhibited a strongly coupled interface, enhanced electron transfer, and higher half-wave potential compared to PtNi/NC and commercial Pt/C.